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NASA Laser Technology Tracks Earth's Ice Sheets

Friday, 31 January 2014

A photon-counting technique will allow NASA researchers to track the melt or growth of Earth’s frozen regions.

CESat-2 is tasked with measuring elevation across Earth's entire surface, including vegetation and oceans, but with a focus on change in the frozen areas of the planet, where scientists have observed dramatic impacts from climate change. There, two types of ice – ice sheets and sea ice – reflect light photons in different patterns. Ice sheets and glaciers are found on land, like Greenland and Antarctica, and are formed as frozen snow and rain accumulates. Sea ice, on the other hand, is frozen seawater, found floating in the Arctic Ocean and offshore of Antarctica.

"Using the individual photons to measure surface elevation is a really new thing," said Ron Kwok, a senior research scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "It's never been done from orbiting satellites, and it hasn't really been done much with airborne instruments, either."

Question of the Week

This week's Question: This month, the Federal Aviation Administration proposed long-awaited rules on the commercial use of small drones, requiring operators to be certified, fly only during daylight, and keep their aircraft in sight. The ruling,...